The present invention relates to an improved structure of sealed lead acid storage battery which makes it possible to produce the battery with a high rationality and reliability, and more particularly, to an improved structure of a sealed lead acid storage battery comprising a battery container, a plurality of cells of the same shape arranged in one row or two parallel rows in the container and groups of electrode plates arranged in each of the cells, in which the leading electrode poles of the groups of electrode plates are positioned on the same side of the cells in each of the rows of cells, and to an improved structure of a lid for the container including the output and input terminal system.
The arrangement of groups of electrode plates in a multi-cell chamber type monoblock battery container for conventional sealed lead acid storage batteries wherein the respective cells are arranged in two rows parallel to each other, will be explained below referring to FIG. 1.
As shown in FIG. 1, groups of electrode plates 1 are contained in each cell chamber 3 of battery container 2. The cells containing the groups of electrode plates 1 are arranged in the order of cells I-VI turning at III and IV and are connected by connectors 4 in such a manner that they are totally connected in the U-shaped form. On the other hand, the electrode poles 6 of the groups of electrode plates 1 for respective output and input terminals 5 and 5' are positioned outwardly both in end cells I and VI at the right end as shown in FIG. 1. In the batteries of this sort the output and input terminals 5 and 5' for the positive and negative electrodes are arranged at the positions near both the end portions in the upper part of the battery in relation with apparatuses in which it is used. Because of such a structure, the groups of electrode plates 1 contained in the respective cells arranged in two rows in the monoblock type battery container 2 require two shape types of the groups, A and B, as shown in FIG. 1, which are different in the structure of providing the positive and negative electrode poles 6 of the respective groups of electrode plates. The requirement of the two types of groups of electrode plates for one sealed lead acid storage battery causes increase in the number of elements for fabrication of battery, especially for assembling the groups of electrode plates in the battery and the number of steps for fabrication and in addition involves a high possibility of producing defective batteries owing to the risk that the positive and negative electrodes are erroneously inversely assembled or the shape type of the groups of electrode plates are confused.
Furthermore, in the case of the respective cells of the battery being connected by cell connectors 4 in one row in the order of I-III as shown in FIG. 2, the electrode poles 6 of the groups of electrode plates 1 for the output and input terminals 5 and 5' are positioned at the same side in the left and right end cells I and III of the battery. This case also requires a plurality of types of the groups of electrode plates and, as mentioned above, there are the problems of increase in the number of elements for fabrication of batteries and the number of elements-assembling steps for fabrication, so that production of defective batteries may occur.
On the other hand, output and input terminals 5 and 5' of a battery are usually welded just above the electrode poles 6 and are connected in the form of an extended electrode pole, and the indented portions of a lid are filled with an adhesive, so that the surrounding of the welded portion is protected with the adhesive to integrate with the lid and to seal the battery. However, in the case of such a structure, the distance of the output and input terminals 5 and 5' from the electrode poles 6 are short, and when a mechanical force is applied in connecting to or releasing from an external apparatus used, a sulfuric acid electrolyte permeate along the electrode poles 6 and enters the back side of the output and input terminals 5 and 5', which causes immediate corrosion of the terminals. Therefore, U.S. Pat. No. 4,563,402 proposed to improve the structure per se of the output and input terminals, thereby reducing the mechanical force applied to adhesive 7. However, this proposed structure of the output and input terminals is complicated, which causes the elements for fabrication of batteries to be complicated or the number of assembling steps for fabrication to increase.
FIG. 3 shows a cross-sectional view of a part of conventional monoblock battery container 2 and lid 8 when the container and the lid were fixed to each other with an adhesive. The container comprises cells containing the groups of electrode plates 1 assembled therein in the assembling steps before fixing with adhesive 7, and the cells are connected by the connectors 4. The lid 8 has groove 9 provided along the periphery thereof in which the periphery of the opening of the battery container is fitted. In integrating the lid 8 and the battery container 2, the portions in which the adhesive 7 is charged are four corners (not shown in FIG. 3) and pots such as reservoirs (also not shown in FIG. 3) into which the connectors 4 are fitted, which both are provided in the inside of the lid. The adhesive flows into the whole of the groove 9 communicating with these portions.